No. Action Bubbling does not work by convention because we have no way to identify the convention. Because the ViewModel being bound does not container the method which can be matched to the control, we pass over the named control. There's no way to know
that that control should bubble an action.

Thanks for taking the time my question. Since this is the first time we write I'd like to thank you for this very good framework (which should be rewarded by a title like MVP BTW ;)

Allow me to dissect your sentences since I would like to get some deeper knowledge about CM

"No. Action Bubbling does not work by convention because we have no way to identify the convention. "

Can you go a bit deeper here? Clearly, there is a way to identify the convention if you use the following syntax<Button cal:Message.Attach="MethodA">Click</Button> (first notation)
But there isn't when you use this syntax <Button x:Name="MethodA">Click</Button> (second notation)
A good question to ask then is what is the difference between the 2 syntaxes and what do we give up when we wish to use the second notation?Or, what do we gain by using the first?

"Because the ViewModel being bound does not container the method which can be matched to the control, we pass over the named control.There's no way to know that that control should bubble an action."

Now that makes me think that if we use the the second notation then you communicate to CM that you expect the handler to be in the viewmodel to which the control is bound.What does CM prevent to bubble it by default even though it's possible that there is no
handler?

*Is it for performance reasons that the second nation doesn't bubble up the message?*